1. Field of the Invention
The present invention relates to an image pick-up apparatus for picking up object information from different directions on a light-receiving surface of one image pick-up device with a plurality of image forming lenses, and a portable telephone utilizing the image pick-up apparatus.
2. Description of the Background Art
The conventional image pick-up apparatuses of the above-mentioned type include, for instance, those having a structure shown in FIGS. 25A and 25B. FIG. 25A shows a front view and a side view of the conventional image pick-up apparatus, and FIG. 25B is a phantom diagram of the side view. As shown in FIGS. 25A and 25B the image pick-up apparatus includes an image forming lens 2, lens-barrels 101 and 102, and a package 13. Package 13 is box-like and its interior has a cavity structure, and an image pick-up device 3 having a light-receiving surface 3a is mounted in the cavity portion. Here, image pick-up device 3 is electrically connected to a circuit pattern portion integrally provided to package 13 by wire bonding packaging and the like, not shown, and further, a space in which image pick-up device 3 is disposed is sealed with a translucent plate 4. Lens-barrel 102 is fixed to package 13 using an adhesive or the like, not shown, and is assembled with lens-barrel 101 by a screw portion, not shown. Lens-barrels 101 and 102 are formed such that focus adjustment of image forming lens 2 can be performed using the screw portion, not shown. In such a conventional image pick-up apparatus, object information is condensed by image forming lens 2 and image is formed on light-receiving surface 3a portion on image pick-up device 3. The information of an object formed as image on light-receiving surface 3a is subjected to a photoelectric conversion and is output as an electrical signal.
The conventional image pick-up apparatus is configured in the above-described manner so that, in the case of a digital camera and the like, there is a need to position a monitor portion, which shows the picked-up image, on the opposite surface from the direction which the image pick-up apparatus faces in order to allow the user to confirm the condition in which the picked-up image is picked up within a monitor frame. On the other hand, in the case of a portable telephone or the like provided with an image pick-up apparatus, possible uses include transmitting and receiving a picked-up image on a communication link of the portable telephones, and two kinds of usage are possible: picking up an image of a self-portrait and transferring data thereof; and picking up an image of an object in the surroundings, for instance, an object in the opposite direction, and transferring data thereof. Thus, two kinds of usage of the image pick-up of a self-portrait and the image pick-up of the opposite direction are desirable in an image pick-up apparatus mounted on a portable telephone; however, since the conventional image pick-up apparatus can only pick up the object information from one direction as described above, it is required that the image pick-up apparatus itself be mechanically rotated to face the direction of the object to be picked up in order to allow image pick-up in both directions, i.e., image pick-up of a self-portrait and that of the opposite direction.
Portable equipment as represented by portable telephones, however, is daily subjected to extremely bad conditions of use such as dropping of the equipment and application of pressure which do not normally occur with electrical equipment. It is, therefore, not desirable to provide a mechanical operating portion such as a rotational portion on a location that is exposed on the outside from the viewpoint of structural strength. In addition, when the image pick-up apparatus is not mechanically rotated, the equipment provided with the image pick-up apparatus itself must be directed toward the object upon performing image pick-up of the opposite direction. Under this circumstance, however, the condition of the picked-up image shown on a display portion of the portable telephone cannot be confirmed so that it is difficult, for instance, to make an adjustment to locate the object in the central portion of a screen. Although the above problem is stated based on the assumption that the image pick-up apparatus is mounted in the same direction as a liquid crystal display portion of the portable telephone, it is possible to mount the image pick-up apparatus facing the opposite direction from the start. In this case, however, a similar problem occurs when attempting image pick-up of a self-portrait. In order to solve these problems, it is possible to mount a plurality of image pick-up apparatuses to effect image pick-up of both directions, but the cost would inevitably increase and it may also lead to graver problems of an enlarged form and increased weight, which are likely to degrade the commercial value of a portable equipment.
Therefore, an image pick-up apparatus has been contemplated which allows image pick-up of object information from two different directions using one image pick-up device, a beam reflecting component such as a prism mirror, and two image forming lenses, and which performs image pick-up of one of the two directions by reflecting an optical path with the prism mirror. In this case, however, it is required that an external shutter or the like switch the direction of image pick-up to either one of the two directions, or that the object information from the two directions be separated inside the image pick-up apparatus by providing a structure such as a divider plate for separating the light regions of the respective object information such that the object information from two different directions do not interfere with one another while object information from both directions are constantly being picked up. In the former case, switching of an external shutter is performed through mechanical operation by the user. A switch or the like for switching the external shutter, however, emerges on the outside of the equipment, which, like the previously described rotational structure, gives rise to the problem related to structural strength in the equipment such as a portable telephone. Moreover, in the latter case, it is difficult to realize light region separation of object information from two directions on the image pick-up device using a divider plate and the like, since the divider plate is a minute component, and assembly must be effected with high accuracy.
The present invention is made to solve the above-described problems. One object of the present invention is to provide an image pick-up apparatus that is capable of picking up images from different directions using one image pick-up device while eliminating the need to switch the image pick-up directions with an external mechanism, and a further object is to provide a portable telephone incorporating such an apparatus.